On a day of low scoring at the Hualalai course, Purtzer recorded eight birdies to go along with an eagle at the par-5 seventh.
Purtzer birdied the first two holes en route to a front nine of 30. He started the back nine with two straight birdies.
"It's kind of a building week," Purtzer said. "I didn't feel like I was very prepared coming over here. I started hitting the ball solid. I hit the driver really good today. That was the key."
Bernhard Langer, starting his first full season on the Champions Tour, shot a 66.
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